CN105324506A - High-strength plated steel sheet having superior plating properties, workability, and delayed fracture resistance, and method for producing same - Google Patents

High-strength plated steel sheet having superior plating properties, workability, and delayed fracture resistance, and method for producing same Download PDF

Info

Publication number
CN105324506A
CN105324506A CN201480035852.2A CN201480035852A CN105324506A CN 105324506 A CN105324506 A CN 105324506A CN 201480035852 A CN201480035852 A CN 201480035852A CN 105324506 A CN105324506 A CN 105324506A
Authority
CN
China
Prior art keywords
steel sheet
less
layer
oxide layer
inner oxide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201480035852.2A
Other languages
Chinese (zh)
Other versions
CN105324506B (en
Inventor
池田宗朗
中屋道治
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobe Steel Ltd
Original Assignee
Kobe Steel Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kobe Steel Ltd filed Critical Kobe Steel Ltd
Publication of CN105324506A publication Critical patent/CN105324506A/en
Application granted granted Critical
Publication of CN105324506B publication Critical patent/CN105324506B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
    • C23C2/06—Zinc or cadmium or alloys based thereon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/01—Layered products comprising a layer of metal all layers being exclusively metallic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/01—Layered products comprising a layer of metal all layers being exclusively metallic
    • B32B15/012—Layered products comprising a layer of metal all layers being exclusively metallic one layer being formed of an iron alloy or steel, another layer being formed of aluminium or an aluminium alloy
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/01—Layered products comprising a layer of metal all layers being exclusively metallic
    • B32B15/013—Layered products comprising a layer of metal all layers being exclusively metallic one layer being formed of an iron alloy or steel, another layer being formed of a metal other than iron or aluminium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/043—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/18—Layered products comprising a layer of metal comprising iron or steel
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/004—Heat treatment of ferrous alloys containing Cr and Ni
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0236—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0257—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment with diffusion of elements, e.g. decarburising, nitriding
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/561—Continuous furnaces for strip or wire with a controlled atmosphere or vacuum
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0222—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating in a reactive atmosphere, e.g. oxidising or reducing atmosphere
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0224—Two or more thermal pretreatments
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
    • C23C2/36—Elongated material
    • C23C2/40—Plates; Strips
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
    • C23C28/322—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer only coatings of metal elements only
    • C23C28/3225—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer only coatings of metal elements only with at least one zinc-based layer
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
    • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
    • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
    • C23C28/345—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one oxide layer
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C30/00—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C30/00—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
    • C23C30/005—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process on hard metal substrates
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/10—Oxidising
    • C23C8/16—Oxidising using oxygen-containing compounds, e.g. water, carbon dioxide
    • C23C8/18—Oxidising of ferrous surfaces
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/002—Bainite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12736—Al-base component
    • Y10T428/1275—Next to Group VIII or IB metal-base component
    • Y10T428/12757—Fe
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12785—Group IIB metal-base component
    • Y10T428/12792—Zn-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12785—Group IIB metal-base component
    • Y10T428/12792—Zn-base component
    • Y10T428/12799—Next to Fe-base component [e.g., galvanized]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12951—Fe-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12951—Fe-base component
    • Y10T428/12958—Next to Fe-base component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12771—Transition metal-base component
    • Y10T428/12861—Group VIII or IB metal-base component
    • Y10T428/12951—Fe-base component
    • Y10T428/12972—Containing 0.01-1.7% carbon [i.e., steel]

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Coating With Molten Metal (AREA)

Abstract

Provided are an alloyed hot dip galvanized steel sheet and a hot dip galvanized steel sheet having superior plating properties, workability in terms of bending workability and hole-expandability, and delayed fracture resistance, and furthermore superior shock absorption resistance of at least 980 MPa. The high-strength plated steel sheet has a plating layer on the surface of a base material steel sheet, contains predetermined steel components, and has, in sequence from the interface between the base material steel sheet and the plating layer towards the base material steel sheet side, a soft layer having a Vickers hardness of no greater than 90% of the Vickers hardness at the t/4 section of the base material steel sheet, where t is the thickness of the base material steel sheet, and a hard layer configured from a structure having primarily martensite and bainite. The average depth (D) of the soft layer is at least 20 [mu]m, and the average depth (d) of an inner oxide layer is at least 4 [mu]m and less than D.

Description

The high strength coated steel sheet of plating, processibility and delayed fracture resistance characteristics excellence and its manufacture method
Technical field
The present invention relates to a kind of tensile strength and be more than 980MPa and the equal excellent high strength coated steel sheet of plating, the processibility comprising bendability and hole expandability and delayed fracture resistance characteristics and its manufacture method.Coated steel sheet of the present invention comprises hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel plate.
Background technology
Hot-dip galvanized steel sheet general in the field such as automobile or conveyor and alloyed hot-dip galvanized steel plate are except being required high strength, also be required the excellent in workability of bendability and hole expandability (stretch flangeability), be required that delayed fracture resistance characteristics is excellent further.Be required that shock-resistant absorptivity is also excellent in addition.
In order to ensure high strength and processibility, effectively in steel, more add the strengthening elements such as Si or Mn.But Si and Mn is easily oxidizable element, being formed in surperficial Si oxide compound or Mn oxide compound etc. obviously can reduce the wettability of galvanizing, produces the problems such as plating of failing.
Therefore, for the coated steel sheet containing more Si or Mn, the various technology in order to improve processibility etc. has been proposed.
In patent documentation 1, such as disclose tensile strength be more than 590MPa and the hot-dip galvanized steel sheet of the corrosion resistance excellent of bendability and processing department.Specifically, in patent documentation 1, in order to suppress to be formed in the generation of flex-crack (flexcrack) caused by the inner oxide layer of steel plate side and the damage of plated film from the interface between steel plate and coating layer, the growth of Decarburized layer is set as significantly faster than the growth of inner oxide layer.In addition, the near surface tissue that the mode further disclosing the lower thickness of the inner oxide layer making to be formed because of decarburization in ferrite area is controlled.
In addition, disclose in patent documentation 2 resistance to fatigue, hydrogen embrittlement resistance (with delayed fracture resistance characteristics synonym), bendability excellence tensile strength be the hot-dip galvanized steel sheet of more than 770MPa.Specifically, in patent documentation 2, steel plate portion comprises: the soft layer directly contacted with the interface of coating layer; And set ferrite as the soft layer of the maximum tissue of area ratio.In addition, further disclose the hot-dip galvanized steel sheet meeting d/4≤D≤2d, wherein, D is the thickness of described soft layer, and d is the degree of depth being present in steel plate skin section and counting from the interface of coating layer and substrate steel containing the oxide compound of more than a kind in Si and Mn.
Patent documentation 1: No. 2011-231367, Japanese Laid-Open Patent Publication
Patent documentation 2: No. 4943558th, Japanese patent gazette
Summary of the invention
The problem to be solved in the present invention
As mentioned above, proposed the various technology that the processibility etc. of the coated steel sheet containing more Si and Mn is improved in the past.But, expect to provide a kind of and not only had various characteristics that this coated steel sheet is required (that is: the processibility of the high strength of more than 980MPa, plating, bendability and hole expandability and delayed fracture resistance characteristics) but also the technology of shock-resistant absorptivity excellence concurrently.
The present invention does in view of the foregoing, its object is to provide the processibility of a kind of plating, bendability and hole expandability and delayed fracture resistance characteristics excellent, and the also excellent tensile strength of shock-resistant absorptivity is the hot-dip galvanized steel sheet of more than 980MPa and alloyed hot-dip galvanized steel plate and its manufacture method.
For the scheme of dealing with problems
The tensile strength involved in the present invention that can solve the problem is the high strength coated steel sheet of more than 980MPa is the coated steel sheet on the surface of base steel sheet with dip galvanized or alloyed hot-dip zinc-coated layer, its main points are, (1) described base steel sheet is in mass % containing C:0.05% to 0.25%, Si:0.5% to 2.5%, Mn:2.0% to 4%, P: more than 0% and less than 0.1%, S: more than 0% and less than 0.05%, Al:0.01% to 0.1%, N: more than 0% and less than 0.01%, surplus is iron and inevitable impurity, (2) from the interface between described base steel sheet and described coating layer, basad steel plate side comprises successively: inner oxide layer, comprise the oxide compound be selected from by least one in the group that Si and Mn is formed, soft layer, comprises described inner oxide layer, and, when the thickness of slab of described base steel sheet is set to t, there is the Vickers' hardness of less than 90% of the Vickers' hardness at the t/4 position of described base steel sheet, and hard layer, comprise the tissue based on martensite and bainite, wherein, the mean depth D of described soft layer is more than 20 μm, and the mean depth d of described inner oxide layer is more than 4 μm and is less than described D.
In preferably embodiment of the present invention, described base steel sheet is further containing being selected from by Cr in mass %: more than 0% and less than 1%, Mo: more than 0% and less than 1% and B: at least one more than 0% and in less than 0.01% group formed.
In preferably embodiment of the present invention, described base steel sheet is further containing being selected from by Ti in mass %: more than 0% and less than 0.2%, Nb: more than 0% and less than 0.2% and V: at least one more than 0% and in less than 0.2% group formed.
In preferably embodiment of the present invention, described base steel sheet is further containing being selected from by Cu in mass %: more than 0% and less than 1% and Ni: at least one more than 0% and in less than 1% group formed.
In preferably embodiment of the present invention, the mean depth d of described inner oxide layer and the mean depth D of described soft layer meets the relation of D > 2d.
In addition, the manufacture method of the present invention that can solve the problem is the method for the manufacture of any one high strength coated steel sheet above-mentioned, its main points are to comprise successively: hot-rolled step, at the temperature more than 600 DEG C by meet described composition of steel hot rolling after coiler plate; Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm; Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.
In addition, another manufacture method of the present invention that can solve the problem is the method for the manufacture of any one high strength coated steel sheet above-mentioned, its main points are to comprise successively: hot-rolled step, at the temperature more than 500 DEG C by meet described composition of steel hot rolling after coiler plate; Incubation step, is incubated more than 80 minutes at the temperature more than 500 DEG C; Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm; Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.
The effect of invention
Coated steel sheet of the present invention basad steel plate side from the interface between coating layer and base steel sheet comprises successively: comprise the inner oxide layer be selected from by the oxide compound of at least one in the group that Si and Mn is formed; Comprise the soft layer in the region of this inner oxide layer; And beyond this soft layer based on the hard layer of martensite and bainite, wherein, especially control to be more than 4 μm apply flexibly as hydrogen catches position by thicker for the mean depth d of inner oxide layer, therefore achieve and effectively can suppress hydrogen embrittlement, and the processibility of bendability and hole expandability and the equal excellent tensile strength of delayed fracture resistance characteristics are the high strength coated steel sheet of more than 980MPa.Preferably, the mean depth d being suitable for controlling inner oxide layer and the relation of the mean depth D of the soft layer in the region comprising this inner oxide layer, therefore especially further increase bendability and delayed fracture resistance characteristics.
Accompanying drawing explanation
Fig. 1 is the schematic illustration from the Rotating fields of the basad steel plate side in the interface between coating layer and base steel sheet in coated steel sheet of the present invention.
Fig. 2 is the explanatory view of the mean depth d of the inner oxide layer measured in coated steel sheet of the present invention.
Fig. 3 is mean depth D in order to determine soft layer and the explanatory view located of the Vickers' hardness used.
Embodiment
The present inventor is in order to provide the high strength of a kind of more than 980MPa of having and the even shock-resistant absorptivity of plating, processibility and delayed fracture resistance characteristics is excellent high strength coated steel sheet, wherein base steel sheet contains more Si and Mn, is focussed in particular on the Rotating fields from the basad steel plate side in the interface between coating layer and base steel sheet and is repeatedly studied.Found that, as shown in the schematic diagram of Fig. 1 described later, inner oxide layer can be made to catch position as hydrogen when following (I) and (II) and play function, effectively can suppress hydrogen embrittlement, therefore desired object can be reached, that is: (I) make from the Rotating fields of the basad steel plate side in the interface between coating layer and base steel sheet comprise possess inner oxide layer soft layer and this soft layer beyond based on the hard layer of martensite and bainite, wherein said inner oxide layer contains the oxide compound be selected from by least one in the group that Si and Mn is formed, (II) control to be more than 4 μm by thicker for the mean depth d of inner oxide layer, in addition, also find: (III) preferably, by mean depth d and the described relation possessing the mean depth D of the soft layer of internal oxidation layer region of the described inner oxide layer of suitable control, come especially to make bendability and delayed fracture resistance characteristics improve further.Like this, the present inventor completes the present invention.
In this manual, coated steel sheet comprises hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel plate.In addition, in this manual, base steel sheet refers to the steel plate formed before dip galvanized or alloyed hot-dip zinc-coated layer, and is distinguished with described coated steel sheet.
In addition, in this manual, so-called high strength refers to that tensile strength is more than 980MPa.
In addition, in this manual, so-called excellent in workability refers to that bendability and hole expansibility are for excellent.Specifically, when measuring these characteristics utilizing in embodiment described later described method, being called as " excellent in workability " of qualified benchmark in embodiment is met.
As mentioned above, coated steel sheet of the present invention has dip galvanized or alloyed hot-dip zinc-coated layer (following, sometimes to represent them with coating layer) on the surface of base steel sheet.Further, the invention is characterized in that basad steel plate side has following (A) Rotating fields to (C) successively from the interface between base steel sheet and coating layer.
(A) inner oxide layer: it comprises the layer be selected from by the oxide compound of at least one in the group that Si and Mn is formed.The mean depth d of inner oxide layer 3 is more than 4 μm and is less than the mean depth D of soft layer described in (B) described later.
(B) soft layer: it comprises described inner oxide layer, when the thickness of slab of described base steel sheet is set to t, has the Vickers' hardness of less than 90% of the Vickers' hardness at the t/4 position of described base steel sheet.The mean depth D of soft layer is more than 20 μm.
(C) hard layer: comprise the tissue based on martensite and bainite.Wherein, " with ... be main body " refer to when utilizing the method recorded in embodiment described later and measuring tissue ratios, bainite and martensitic total area ratio are 80 more than area %, and ferritic area ratio is 0 more than area % and 5 below area %.
Below, with reference to Fig. 1, explain successively and give (A) described in feature to the Rotating fields of (C) to the present invention.As shown in Figure 1, the Rotating fields of base steel sheet 2 side of coated steel sheet of the present invention comprises from basad steel plate 2 side, the interface between coating layer 1 and base steel sheet 2: the soft layer 4 of described (B); And the hard layer 5 of described (C), this hard layer 5 is positioned at the inside 6 of base steel sheet 2 side than soft layer 4.Wherein, the soft layer 4 of described (B) comprises the inner oxide layer 3 of described (A).In addition, hard layer 5 is present in inner 6, as long as meet the prerequisite of hard layer 5 described later, and the existence form not in restricted internal 6.Therefore, soft layer 4 and hard layer 5 can exist continuously, also can exist discontinuously.
(A) inner oxide layer
First illustrate, the part being directly contacted with the interface of coating layer 1 and base steel sheet 2 has the inner oxide layer 3 that mean depth d is more than 4 μm.Wherein, mean depth refers to the mean depth counted from described interface, for the measuring method that it is detailed, uses Fig. 2 to be illustrated in the embodiment that will be described below.
Described inner oxide layer 3 contains: the oxide compound comprising at least one in Si and Mn; And Si and the Mn depleted layer that around it, solid solution Si and/or solid solution Mn is less because Si and/or Mn forms oxide compound.
Master of the present invention is characterised in that and controls to be more than 4 μm by thicker for the mean depth d of described inner oxide layer 3.Thus, this inner oxide layer can be caught position as hydrogen and effectively utilize, can hydrogen embrittlement be suppressed, and improve bendability, hole expandability and delayed fracture resistance characteristics.
In addition, as the present invention, base steel sheet containing easily oxidizable elements such as more Si and Mn, when annealing (oxidation step in continuous hot-dipping galvanizing production line described later and reduction step), easily forming the complex oxide film of Si and Mn, can reduce plating on this base steel sheet surface.Therefore, in order to avoid this problem, the method that known employing is following: make the surface oxidation of base steel sheet and after generating Fe oxide film, carry out anneal (reduced anneal) in hydrogeneous atmosphere under oxidizing atmosphere.In addition, knownly also adopt following method: the top layer making easily oxidizable element be fixed on base steel sheet as oxide compound by controlling furnace atmosphere is inner, the easily oxidizable element being solid-solubilized in base steel sheet top layer is reduced, thus prevents easily oxidizable element from forming oxide film on the surface of base steel sheet.
But, the present inventor is found by research: when adopting the general oxidation reduction process being used for the base steel sheet containing more Si and Mn being carried out to plating, under nitrogen atmosphere when reducing, hydrogen infiltrates to base steel sheet, thus the reduction of the bendability produced because hydrogen embrittlement causes and hole expandability; In order to improve the reduction of these performances, effective measures apply flexibly the oxide compound be selected from by least one in the group that Si and Mn is formed.Specifically, find that described oxide compound can be used as hydrogen catches position, it can prevent hydrogen infiltration to the inside of base steel sheet when reducing, improve bendability, hole expandability and delayed fracture resistance characteristics, in order to make it effectively play relevant effect, integral is is formed as more than 4 μm by thicker for the mean depth d of the inner oxide layer containing described oxide compound.
In the present invention, the upper limit of the mean depth d of inner oxide layer is at least less than the mean depth D of (B) described later soft layer.The upper limit of described d is preferably less than 30 μm.Its reason is: in order to make inner oxide layer thickening, needs to be held in high-temperature area for a long time after hot rolling reeling, but owing to being subject to the restriction on production efficiency and equipment, therefore probably becomes above-mentioned preferred value.Described t more preferably less than 18 μm, is more preferably less than 16 μm.In addition, described d is preferably more than 6 μm, is more preferably more than 8 μm.
Say again, in the present invention, preferred: the mode meeting D > 2d with the relation of the mean depth D making the mean depth d of described inner oxide layer and (B) described later soft layer controls the mean depth d of this inner oxide layer, bendability and delayed fracture resistance characteristics can be improved further thus, especially can improve bendability.Relative to this, the hot-dip galvanized steel sheet meeting d/4≤D≤2d is disclosed in aforesaid patent documentation 2, the thickness D of the degree of depth d wherein existing for oxide compound and soft layer roughly corresponds to the mean depth d of inner oxide layer and the mean depth D of soft layer that record in the present invention, and the control policy of patent documentation 2 is completely different from the described relational expression specified in the present invention (D > 2d).And, described patent documentation 2 describes the scope of the degree of depth d on the basis of the relation meeting aforesaid d/4≤D≤2d existing for control oxide substantially, and therefore not having illustrated is completely the basic conception of more than 4 μm by thicker for the mean depth d of inner oxide layer control.Certainly, do not record the effect effectively playing therefrom and catch position as hydrogen, the effect of the present invention improved to make bendability, hole expandability and delayed fracture resistance characteristics yet.
In addition, in the present invention, in order to the mean depth d of described inner oxide layer is controlled to be more than 4 μm, need the mean depth of the inner oxide layer of the cold-rolled steel sheet entered before continuous hot-dipping galvanizing production line to control to be more than 4 μm.For detailed content, describe in manufacture method below.That is, as shown in embodiment described later, pickling, cold rolling after inner oxide layer inherited the inner oxide layer entered after plating lines in the final coated steel sheet obtained.
(B) soft layer
In the present invention, as shown in Figure 1, soft layer 4 is the layers in the region of the inner oxide layer 3 comprising described (A), and has the Vickers' hardness of less than 90% of the Vickers' hardness at the t/4 position of base steel sheet 2.For the detailed measuring method of described Vickers' hardness, be illustrated in the embodiment that will be described below.
Described soft layer is the soft tissue that Vickers' hardness is lower than (C) described later hard layer, and deformability is excellent, therefore especially makes bendability improve.That is when bending machining, the skin section of base steel sheet becomes the starting point of fracture, but as representative of the present invention, by forming the soft layer of regulation on the top layer of base steel sheet, bendability is especially made to improve.And by forming described soft layer, the starting point ruptured when can prevent the oxide compound in described (A) from becoming bending machining, only can enjoy aforesaid advantage of catching position as hydrogen.Thus, bendability not only can be made to improve further, delayed fracture resistance characteristics can also be made to improve further.
In order to the effect that the formation effectively playing this soft layer brings, the mean depth D of described soft layer is set to more than 20 μm.Described T is preferably more than 22 μm, is more preferably more than 24 μm.On the other hand, if the mean depth D of described soft layer is blocked up, then the intensity of coated steel sheet self reduces, and therefore its upper limit is preferably established less than 100 μm.Described D is more preferably less than 60 μm.
(C) hard layer
In the present invention, as shown in Figure 1, hard layer is formed in the private side being positioned at base steel sheet 2 than the soft layer 4 of described (B), and comprises the tissue based on martensite and bainite.The martensite of described hard layer 5 also can be the martensite after tempering.Wherein, " with ... be main body " refer to when measuring tissue ratios utilizing in embodiment described later described method, in organized whole, bainite and martensitic total area ratio are 80 more than area %, further, in organized whole, ferritic area ratio is 0 more than area % and 5 below area %.Bainite and the martensitic total area ratio of hard layer are the bigger the better, and are preferably 93 more than area %.On the other hand, ferritic area ratio is the smaller the better, is preferably 5 below area %, is more preferably 3 below area %, most preferably is 0 area %.
Hard layer, except above-mentioned tissue, can also comprise the tissue be inevitably mixed into during fabrication in the scope of not losing effect of the present invention, such as residual γ, perlite etc.This is also only 15 below area % when being organized in its maximum area ratio, the smaller the better.In addition, in table 2 described later, this tissue is recited as " other ".
By forming described hard layer, bendability and hole expandability are improved.That is, generally speaking, by the crackle when soft phase (such as ferrite) stress concentration occurs with the interface of hard phase (such as martensite and bainite) thus causes flex-crack or reaming.Therefore, in order to suppress described crackle, need to reduce the difference of hardness between soft phase and hard phase.So, in the present invention, ratio shared in the tissue of base steel sheet inside for soft ferrite is suppressed, for maximum 5 below area %, make the hard layer based on bainite and martensite.And in described hard layer, owing to inhibit ferritic ratio, therefore yield ratio (YR) uprises, and shock-resistant absorptivity is also improved.
In addition, as mentioned above, as long as hard layer of the present invention comprises bainite and martensite as main body, bainite and martensitic respective ratio there is no any restriction.Its reason is: in the present invention, as long as meet above-mentioned prerequisite, and the above-mentioned effect that the formation that just can play hard layer brings.Therefore, as long as described hard layer meets above-mentioned prerequisite, bainite > martensite, bainite=martensite, these all relations of bainite < martensite can be met.In addition, bainite is only comprised and completely containing martensitic situation and only comprise martensite and completely all within the scope of the invention not involved containing the situation of bainite.Consider from above-mentioned viewpoint, in embodiment described later, bainite and martensite are not observed in difference, and only measure total area, and the result of this mensuration are shown in table 3.
Above, for main feature of the present invention, be namely illustrated from the Rotating fields of the basad steel plate side in the interface between coating layer and base steel sheet.
Then, composition of steel of the present invention is illustrated.
Coated steel sheet of the present invention contains C:0.05% to 0.25%, Si:0.5% to 2.5%, Mn:2.0% to 4%, P: more than 0% and less than 0.1%, S: more than 0% and less than 0.05%, Al:0.01% to 0.1%, N: more than 0% and less than 0.01%, surplus is iron and inevitable impurity.
C:0.05% to 0.25%
C is for improving hardenability, also brings hardening effect to martensite, is important element for the high strength of steel.In order to effectively play this effect, the lower limit of C content is set to more than 0.05%.The lower limit of C content is preferably more than 0.08%, is more preferably more than 0.10%.But if add C too much, then softly become greatly with the difference of hardness of hard phase, processibility and delayed fracture resistance characteristics reduce, and therefore the upper limit of C content are set to 0.25%.The upper limit of C content is preferably less than 0.2%, is more preferably less than 0.18%.
Si:0.5% to 2.5%
Si is the intensity being improved steel by solution strengthening, and is effective element for the raising of processibility.In addition, Si generates inner oxide layer, also has the effect suppressing hydrogen embrittlement.In order to effectively play this effect, the lower limit of Si content is set to more than 0.5%.The lower limit of Si content is preferably more than 0.75%, is more preferably more than 1%.But Si is ferrite generating elements, if add Si too much, then can not suppress ferritic generation, softly become greatly with the difference of hardness of hard phase, processibility reduces.And plating is also deteriorated, therefore the upper limit of Si content is set to 2.5%.The upper limit of Si content is preferably less than 2%, is more preferably less than 1.8%.
Mn:2.0% to 4%
Mn is that hardenability improves element, suppresses ferrite and bainite, generates martensite, contribute to high strength.In order to effectively play this effect, the lower limit of Mn content is set to more than 2.0%.The lower limit of Mn content is preferably more than 2.3%, is more preferably more than 2.5%.But if add Mn too much, then plating reduces, and segregation also becomes remarkable.Further, the grain boundary segregation of P can also be encouraged.Therefore, the upper limit of Mn content is set to 4%.The upper limit of Mn content is preferably less than 3.5%.
P: more than 0% and less than 0.1%
P is the element useful to the strengthening of steel as solution strengthening element.In order to effectively play this effect, the lower limit of P content is set to more than 0%.But, if added too much, then not only make processibility reduce, also can bring the reduction of weldability and toughness, therefore the upper limit of P content is set to less than 0.1%.P content is less is advisable, and is preferably less than 0.03%, is more preferably less than 0.015%.
S: more than 0% and less than 0.05%
S is the element inevitably contained, and generate MnS sulfides, this sulfide becomes the starting point of fracture, likely makes processibility reduce.Therefore, the upper limit of S content is set to less than 0.05%.S content is less is advisable, and is preferably less than 0.01%, is more preferably less than 0.008%.
Al:0.01% to 0.1%
Al works as reductor.In addition, Al and N is combined into as AlN, and causes the miniaturization of austenite particle diameter, and processibility and delayed fracture resistance characteristics are improved.In order to effectively play this effect, the lower limit of Al content is set to more than 0.01%.The lower limit of Al content is preferably more than 0.02%, is more preferably more than 0.03%.But, if add Al too much, then make the inclusiones such as aluminum oxide increase and cause processibility to reduce, also bring the reduction of toughness.Therefore, the upper limit of Al content is set to 0.1%.The upper limit of Al content is preferably less than 0.08%, is more preferably less than 0.05%.
N: more than 0% and less than 0.01%
N is the element inevitably contained, if but content crosses processibility reduction at most.And, when adding B (boron) in steel, generate BN precipitate, hinder the hardenability raising effect of B, therefore reduce N as much as possible and be advisable.So, the upper limit of N content is set to less than 0.01%.The upper limit of N content is preferably less than 0.008%, is more preferably less than 0.005%.
Coated steel sheet of the present invention contains mentioned component, and surplus is iron and inevitable impurity.
In addition, the present invention also can containing, for example lower selective element.
Be selected from by Cr: more than 0% and less than 1%, Mo: more than 0% and less than 1% and B: at least one more than 0% and in less than 0.01% group formed
These elements are effective elements for the intensity rising of steel plate.These elements both can add separately, can combine again add two or more.
Specifically, Cr makes hardenability improve, and contributes to intensity and rises.And Cr suppresses generation and the growth of cementite, contributes to improving bendability.In order to effectively play this effect, the lower limit of Cr content is set to more than 0.01%.But if add Cr too much, then plating reduces, and generates Cr carbide too much, causes processibility to reduce.Therefore, the upper limit of Cr content is preferably less than 1%, is more preferably less than 0.7%, is more preferably less than 0.4%.
For high strength effectively, therefore, the lower limit of Mo content is preferably more than 0.01% to Mo.But if add Mo too much, then described effect is saturated, makes cost uprise.Therefore, the upper limit of Mo is preferably less than 1%, is more preferably less than 0.5%, is more preferably less than 0.3%.
B and Mn is that hardenability improves element equally, is to suppress ferrite and bainite, generates martensite, contribute to the element of high strength.In order to effectively play this effect, the lower limit of B content is preferably more than 0.0002%, is more preferably more than 0.0010%.But if B content is too much, then make hot workability reduce, therefore, the upper limit of B content is preferably less than 0.01%, is more preferably less than 0.0070%, is more preferably less than 0.0050%.
Be selected from by Ti: more than 0% and less than 0.2%, Nb: more than 0% and less than 0.2% and V: at least one more than 0% and in less than 0.2% group formed
These elements are effective elements for the raising for the processibility organizing miniaturization to bring and delayed fracture resistance characteristics.These elements both can add separately, can combine again add two or more.
In order to effectively play above-mentioned effect, Ti, Nb, V lower limit is separately preferably more than 0.01%.But if the content of each element is too much, then generate ferrite, make processibility reduce, therefore, the upper limit of each element is preferably less than 0.2%.Each element is more preferably less than 0.15%, is more preferably less than 0.10%.
Be selected from by Cu: more than 0% and less than 1% and Ni: at least one more than 0% and in less than 1% group formed
Cu and Ni is effective element for high strength.These elements both can add separately, can combine interpolation again.
In order to effectively play above-mentioned effect, Cu, Ni lower limit is separately preferably more than 0.01%.But if the content of each element is too much, then make hot workability reduce, therefore, the upper limit of each element is preferably less than 1%.Each element is more preferably less than 0.8%, is more preferably less than 0.5%.
Above, composition of steel of the present invention is illustrated.
Below, the manufacture method for coated steel sheet of the present invention is illustrated.Manufacture method of the present invention comprises: after hot rolling reeling, is not incubated and carries out the first method of pickling immediately; And be incubated after hot rolling reeling, then carry out the second method of pickling.According to the presence or absence of insulation, the first method (without insulation) is different with the lower limit of the hot-rolling coiling temperature of the second method (having insulation), and step is in addition identical.Below described in detail.
[the first manufacture method (without insulation)]
First manufacture method involved in the present invention is roughly divided into: hot-rolled step; Pickling and cold-rolling step; And oxidation step, reduction step and the plating steps in continuous hot-dipping galvanizing production line (CGL (ContinuousGalvanizingLine)).The invention is characterized in and comprise successively: hot-rolled step, at the temperature more than 600 DEG C, will the coiler plate of above-mentioned composition of steel be met, thus obtain the hot-rolled steel sheet being formed with inner oxide layer; Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm; Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.
Below, be illustrated according to sequence of steps.
First, the hot-rolled steel sheet meeting above-mentioned composition of steel is prepared.Such as, as long as hot rolling is based on common method, in order to prevent the alligatoring of austenite grain, Heating temperature is preferably 1150 DEG C to about 1300 DEG C.In addition, preferably finishing temperature probably being controlled is 850 DEG C to 950 DEG C.
In addition, in the present invention, it is importantly more than 600 DEG C by the oiler temperature control after hot rolling.Thus, inner oxide layer can be formed on the surface of base steel sheet.When coiling temperature is less than 600 DEG C, inner oxide layer can not be formed fully, and the intensity of hot-rolled steel sheet uprises, cold-rolling property is reduced.Coiling temperature is preferably more than 620 DEG C, is more preferably more than 640 DEG C.But if coiling temperature is too high, then black oxide skin (blackscale) is too grown up, and can not be dissolved by pickling, and therefore its upper limit is preferably less than 750 DEG C.
Then, pickling and cold rolling is carried out to the hot-rolled steel sheet obtained by the way, retains more than 4 μm to make the mean depth d of inner oxide layer.The thickness controlling inner oxide layer by controlling acid washing conditions is known scheme, specifically, according to the kind of used pickle solution or concentration etc., the temperature of pickling, time etc. can be controlled aptly, to guarantee the thickness of desired inner oxide layer.
For pickle solution, such as, can adopt the mineral acids such as hydrochloric acid, sulfuric acid, nitric acid.
In addition, generally speaking, if the concentration of pickle solution or temperature high, pickling time is long, then there is inner oxide layer and dissolve and thinning tendency.On the contrary, if the concentration of pickle solution or temperature low, pickling time is short, then can not fully remove black oxide scale layer by pickling.Therefore, such as, when using hydrochloric acid, recommend concentration to control as about 3% to 20%, temperature being controlled to be 60 DEG C to 90 DEG C, is about 35 seconds to 200 seconds by time controling.
In addition, pickling tank number is not particularly limited, and can use multiple pickling tank.And, the pickling inhibitors such as such as amine (i.e. inhibitor) or acid pickling promotor etc. can also be added in pickle solution.
After pickling, carry out cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm.Preferred cold rolling condition cold rolling rate is controlled in the scope for about 20% to 70%.
Then, carry out being oxidized and reducing.
Specifically, first in zone of oxidation, be oxidized with the air-fuel ratio of 0.9 to 1.4.Air-fuel ratio refers to the throughput ratio of combustion gases and air.CO gas is used in embodiment described later.Be oxidized by under the atmosphere that becomes described scope in air-fuel ratio, at Surface Creation Fe oxide film, the generation of complex oxide film plating being brought to dysgenic Si and Mn can be suppressed.And decarburization is also carried out, therefore, it is possible to the soft layer desired by being formed, bendability also improves.If air-fuel ratio is less than 0.9, then the generation of described Fe oxide film becomes insufficient, can not suppress the generation of described complex oxide film, thus cause plating to reduce.Further, decarburization also becomes insufficient, and can not form sufficient soft layer, therefore bendability also reduces.On the other hand, if air-fuel ratio is up to more than 1.4, then generate oxide film too much, can not reduce fully in follow-up reduction furnace, plating is hindered.Preferably air-fuel ration control is more than 1.0 and less than 1.2.
In described zone of oxidation, the control particularly important of air-fuel ratio, condition in addition can adopt the method usually used.Such as, the lower limit of described oxidizing temperature is preferably more than 500 DEG C, is more preferably more than 750 DEG C.In addition, the upper limit of described oxidizing temperature is preferably less than 900 DEG C, is more preferably less than 850 DEG C.
Then, in zone of reduction, under a hydrogen atmosphere oxide film is reduced.In the present invention, in order to suppress ferrite to obtain desired hard layer, need to heat, at Ac in austenite one phase district 3point is to Ac 3equal thermal treatment is carried out in the scope of point+100 DEG C.If soaking temperature is lower than Ac 3point, then ferrite becomes too much; On the other hand, if more than Ac 3point+100 DEG C, then austenite alligatoring, makes processibility reduce.Soaking temperature is preferably Ac 3point more than+15 DEG C and Ac 3point less than+85 DEG C.
In addition, in the present invention, Ac 3point can calculate based on following formula (i).In formula, [] represents the content (quality %) of each element.This formula " Lesley's ferrous materials " (Wan Shan Co., Ltd. distribution, WilliamC.Leslie work, the 273rd page) on the books.
Ac 3(℃)＝910－203×[C] 1/2－15.2×[Ni]+44.7×[Si]+104×[V]+31.5×[Mo]+13.1×[W]－{30×[Mn]+11×[Cr]+20×[Cu]－700×[P]－400×[Al]－120×[As]-400×[Ti]}(i)
In described reduction furnace, the control particularly important of soaking temperature, condition in addition can adopt the method usually used.Such as, preferred: the atmosphere of zone of reduction comprises hydrogen and nitrogen, and hydrogen concentration is controlled in the scope for about 5 volume % to 25 volume %.In addition, preferably dew point is controlled as-30 DEG C to-60 DEG C.
In addition, hold-time during equal thermal treatment is not particularly limited, and such as, preferably controlling is 10 seconds to about 100 seconds, and more preferably controlling is 10 seconds to about 80 seconds.
Then, cool.In order to ferritic generation can be suppressed, preferably average cooling rate during cooling is controlled to be more than 5 DEG C/sec, be more preferably more than 8 DEG C/sec.The upper limit of average cooling rate is not particularly limited, but considers the easiness, equipment cost etc. that control base steel sheet temperature, and preferably general control is less than 100 DEG C/sec.Average cooling rate is more preferably less than 50 DEG C/sec, is more preferably less than 30 DEG C/sec.
As long as cooling stops temperature not generating in ferritic temperature province, such as, be preferably cooled to less than 550 DEG C.Cooling stops the lower limit of temperature to be preferably such as more than 450 DEG C, is more preferably more than 460 DEG C, is more preferably more than 470 DEG C.
But method of cooling is not limited to aforesaid way, such as, when plating bath when will be heated to galvanizing after the cooling period, also can be cooled to and stop temperature lower than described preferred cooling.Such as, please refer to the No.11 of table 1 described later.Or, also after being cooled to specified temperature, then water-cooled can be carried out.Please refer to the No.12 of table 1 described later.
Then, galvanizing is carried out according to common method.The method of galvanizing is not particularly limited, and such as, the lower limit of described plating bath is preferably more than 400 DEG C, is more preferably more than 440 DEG C.In addition, the upper limit of described plating bath is preferably less than 500 DEG C, is more preferably less than 470 DEG C.The composition of plating bath is not particularly limited, and adopts known galvanizing to bathe.In addition, the cooling conditions after galvanizing is also not particularly limited, and such as, is preferably controlled, for more than about 1 DEG C/sec, to be more preferably more than 5 DEG C/sec by the average cooling rate being cooled to normal temperature.The upper limit of described average cooling rate not specially provided for, but consider the easiness, equipment cost etc. that control base steel sheet temperature, preferably control as less than about 50 DEG C/sec.Described average cooling rate is preferably less than 40 DEG C/sec, is more preferably less than 30 DEG C/sec.
Further, also optionally and by common method can implement Alloying Treatment, can alloyed hot-dip galvanized steel plate be obtained thus.The condition of Alloying Treatment is also not particularly limited, such as, after carrying out galvanizing under these conditions, preferably at 500 DEG C to (more preferably at 530 DEG C under about 580 DEG C) under about 600 DEG C, keep 5 seconds to about 30 seconds (more preferably keeping 10 seconds to about 25 seconds).If lower than above-mentioned scope, then alloying becomes insufficient; On the other hand, if exceed above-mentioned scope, then alloying can be caused excessively to carry out, coating layer is peeled off, and also easily generates ferrite.Alloying Treatment such as can use process furnace, adopt straight fire or ultrared process furnace etc. to carry out.Heater means is also not particularly limited, such as, can adopt the means that gas heating, induction heater heating (that is utilizing the heating of high-frequency induction heating apparatus) etc. are usual.
After Alloying Treatment, cool according to common method, thus can alloyed hot-dip galvanized steel plate be obtained.Preferably the average cooling rate being cooled to normal temperature is controlled as more than about 1 DEG C/sec.
[the second manufacture method (having insulation)]
Second manufacture method involved in the present invention comprises successively: hot-rolled step, at the temperature more than 500 DEG C by meet described composition of steel hot rolling after coiler plate; Incubation step, is incubated more than 80 minutes at the temperature more than 500 DEG C; Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm; Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.Compared with aforesaid first manufacture method, the difference of described second manufacture method and described first manufacture method is only: the lower limit of the coiling temperature after hot rolling is set to more than 500 DEG C; And incubation step is set after hot-rolled step.Therefore, only this difference is illustrated below.About the step consistent with described first manufacture method, please refer to described first manufacture method.
The reason arranging incubation step is as described above: by insulation, can remain on oxidable humidity province for a long time, can expand the lower limit of the coiling temperature scope that can obtain desired inner oxide layer.In addition, its reason is also: it can possess the top layer that can reduce base steel sheet and inner temperature head and improve the advantage of the homogeneity of base steel sheet.
First, in described second manufacture method, it is more than 500 DEG C by the oiler temperature control after hot rolling.In described second manufacture method, as described later in detail, incubation step is being set thereafter, therefore coiling temperature can be being set lower than the lower limit 600 DEG C of the coiling temperature in aforesaid first manufacture method.Coiling temperature is preferably more than 540 DEG C, is more preferably more than 570 DEG C.In addition, the preferred upper limit of coiling temperature is identical with aforesaid first manufacture method, is preferably less than 750 DEG C.
Then, at the temperature more than 500 DEG C, the hot-rolled steel sheet obtained by the way is incubated more than 80 minutes.Thus, desired inner oxide layer can be obtained.Being incubated to effectively play the described effect brought, preferably described hot-rolled steel sheet such as being put into the device with thermal insulation and being incubated.As long as this device used in the present invention is made up of thermal insulation material and is just not particularly limited, as thermal insulation material, preferably adopt the materials such as such as ceramic fiber.
In order to effectively play above-mentioned effect, under needing the temperature more than 500 DEG C, be incubated more than 80 minutes.Temperature is preferably more than 540 DEG C, is more preferably more than 560 DEG C.In addition, the time is preferably more than 100 minutes, is more preferably more than 120 minutes.In addition, consider pickling, production efficiency etc., preferably the upper limit of described temperature and time probably being controlled is less than 700 DEG C, less than 500 minutes.
Above, first and second manufacture method involved in the present invention is illustrated.
For the coated steel sheet of the present invention obtained by described manufacture method, also can carry out further: various application and application base treatment, such as, carry out the chemical conversion treatment of phosphatizing etc.; And organic coating process, such as carry out the formation etc. of the organic coating of pellicular cascade and so on.
For the coating used in various application, known resin can be used, such as epoxy resin, fluoro-resin, silicone acrylic resin (siliconeacrylicresin), urethane resin, acrylic resin, vibrin, phenol resins, Synolac, melamine resin etc.Consider from corrosion proof viewpoint, be preferably epoxy resin, fluoro-resin, silicone acrylic resin.Together stiffening agent can also be used with described resin.Such as, and coating can also contain known additive, colouring pigments, coupling agent, levelling agent, synergistic agent (intensifier), antioxidant, ultra-violet stabilizer, fire retardant etc.
In the present invention, the form of coating is not particularly limited, and can use the coating of any form, such as solvent system coating, aqueous coating, water-dispersed paint, powder coating, electrophoretic paint etc.And coating process is also not particularly limited, pickling process, rolling method, spray method, curtain coating method, electrophoretic deposition etc. can be used.The thickness of the coating layers such as coating layer, organic coating, chemical conversion treatment coating, film can according to the suitable setting of purposes.
The intensity superelevation of high strength coated steel sheet of the present invention, and processibility (bendability and hole expandability), delayed fracture resistance characteristics are excellent, therefore may be used for automobile strength member, such as anterior or rear portion the pillar such as crash element and center pillar stiffener class, roof stiffener, curb girder, floor component, the pin such as side member, collision energy absorbing box step on the car body component parts such as portion.
, enumerate embodiment below, further illustrate the present invention, but the present invention does not limit by following embodiment, can be changed in the scope being applicable to purport aforementioned, described later and implement, these changes be all contained in technical scope of the present invention.
The application advocates the rights and interests of the right of priority of No. 2014-068539th, the Japanese patent application of filing an application based on No. 2013-147031st, the Japanese patent application of filing an application on July 12nd, 2013 and on March 28th, 2014.The present invention quotes all the elements of the specification sheets of No. 2013-147031st, the Japanese patent application of filing an application on July 12nd, 2013 and No. 2014-068539th, the Japanese patent application of filing an application on March 28th, 2014, for reference.
Embodiment
By containing the composition shown in following table 1 and surplus is the heating of plate blank to 1250 DEG C of iron and inevitable impurity, at finishing temperature 900 DEG C, hot rolling is, after 2.4mm, batch at the temperatures shown in table 2.
For the example No.26 to No.28 of a part, put into afterwards in the heat-proof device of ceramic fiber, be incubated under the conditions shown in Table 2.Utilize the soaking time being arranged on the thermocouple measurement of coil peripheral part more than 500 DEG C.
Then, under the following conditions pickling has been carried out to the hot-rolled steel sheet obtained by the way, then carried out cold rolling with the cold rolling rate of 50%.Thickness of slab after cold rolling is 1.2mm.
Pickle solution: 10% hydrochloric acid, temperature: 82 DEG C, pickling time: as shown in table 2.
Then, in continuous hot-dipping galvanizing production line, anneal (oxidation, reduction) and cooling has been carried out under the conditions shown in Table 2.Now, be set to 800 DEG C with the temperature of the oxidized still arranged in continuous hot-dipping galvanizing production line, hydrogen concentration in reduction furnace is set to 20 volume % (surplus is nitrogen and inevitable impurity) and dew point is set to-45 DEG C controls.In addition, the hold-time under shown in table 2 soaking temperature is all set to 50 seconds.
Then, except following No.10, No.11, all impregnated in the zinc-plated bath of 460 DEG C, after impregnated of about 50 seconds, be cooled to room temperature with the average cooling rate of 10 DEG C/sec, obtain hot-dip galvanized steel sheet (GI) (No.23).About alloyed hot-dip galvanized steel plate (GA), to impregnated in described zinc-plated bath after implementing galvanizing, be heated to 500 DEG C, keep 20 seconds at such a temperature and carried out Alloying Treatment, being then cooled to room temperature (No.1 to No.9, No.12 to No.22, No.24, No.25 to No.28) with the average cooling rate of 10 DEG C/sec.
In addition, about No.10, after being cooled to cooling stopping temperature 200 DEG C described in table 2, being heated to 460 DEG C, then impregnated in zinc-plated bath, obtain GA steel plate by mode similar to the above.In addition, about No.11, as shown in table 2, after being cooled to 600 DEG C with the average cooling rate of 10 DEG C/sec, carrying out water-cooled (WQ (Water-Quenching)), be heated to thereafter 460 DEG C, then impregnated in zinc-plated bath, obtain GA steel plate by mode similar to the above.
For the coated steel sheet obtained by the way that is GI or GA, carry out the evaluation of following characteristic.In addition, as the mean depth of inner oxide layer, as described below, not only coated steel sheet is measured, to pickling, cold rolling after base steel sheet measure similarly, with common reference.This by the coiling temperature, acid washing conditions etc. that control after hot rolling, has obtained the mean depth of desired inner oxide layer in order to confirm in the cold-rolled steel sheet before annealing.
(1) mensuration of the mean depth d of the inner oxide layer in coated steel sheet
If the plate of coated steel sheet is wide is W, the test piece being of a size of 50mm × 50mm is acquired from the position of the W/4 of this coated steel sheet, then, utilize glow discharge luminescence analysis (GD-OES (GlowDischarge-OpticalEmissionSpectroscopy)), analyze respectively for O content, Fe content and Zn content from coating layer surface, and carry out quantitatively.Specifically, utilize the GD-OES device of the GD-PROFILER2 type GDA750 manufactured by the making of hole field, in Ar glow discharge region, high-frequency sputtering is carried out to the surface of described test piece, continuously light splitting is carried out to the isolychn of each element of sputtered O, Fe, Zn in Ar plasma body, has determined the distribution of each amount of element of the depth direction of base steel sheet.Sputtering condition is as described below, and to be set in mensuration region from coating layer surface till the degree of depth 50 μm.
(sputtering condition)
Pulsed sputter frequency: 50Hz
Anode diameter (analysis area): diameter 6mm
Discharge power: 30W
Ar air pressure: 2.5hPa
Analytical results is shown in Fig. 2.As shown in Figure 2, Zn content and Fe content are become the mutually the same position from the surface of coating layer 1 and be set to interface between coating layer 1 and base steel sheet 2.In addition, the mean value of the O content measured at the respectively place of locating of the degree of depth from the surface of coating layer 40 μm to 50 μm is set to the O content mean value of test piece inside, and the scope of higher than it 0.02% that is O content >=(the O content mean value+0.02% of test piece inside) are defined as inner oxide layer, its full depth is set to internal oxidation layer depth.Utilize 3 test pieces to implement same test, its mean value is set to the mean depth d of inner oxide layer.
(2) pickling, cold rolling after the mensuration (reference) of internal oxidation layer depth
Except use pickling, cold rolling after base steel sheet this point except, all calculated the mean depth of inner oxide layer by the mode same with above-mentioned (1).
(3) mensuration of the mean depth D of soft layer
The section at the W/4 position vertical relative to the plate of coated steel sheet wide W direction is exposed, acquire the test piece being of a size of 20mm × 20mm, then, imbedded in resin, and from the interface between coating layer and base steel sheet, towards the thickness of slab t intraassay Vickers' hardness of base steel sheet.Wherein utilize Vickers hardness tester, measure under load is 3gf.Specifically, as shown in Figure 3, the thickness of slab internal depth from the interface between coating layer and mother metal is the beginning that locates of 10 μm, has carried out the mensuration of Vickers' hardness, until the position of the degree of depth 100 μm towards the inner spacing every 5 μm of thickness of slab.Interval between measuring point that is in figure 3 × and × between distance minimumly also have more than 15 μm.Determine Vickers' hardness at each depth location with the number of n=1, investigate the Hardness Distribution of thickness of slab internal direction.Further, the Vickers' hardness at the t/4 position of base steel sheet is also determined by same mode.Further, by with t/4 position Comparatively speaking Vickers' hardness be less than 90% region be set to soft layer, calculate its degree of depth.3 positions in same test piece implement same process, mean value are set to the mean depth D of soft layer.
(4) measuring method of the tissue ratios of coated steel sheet
The section at the W/4 position vertical relative to the plate of coated steel sheet wide W direction is exposed, this section is ground, after carrying out electrolytic polishing further, corrode with nitric acid ethanol, then, utilize SEM (ScanningElectronMicroscope, sweep electron microscope) to this has been observation.When setting the thickness of slab of base steel sheet as t, observation place is t/4 position, and observing multiplying power is 2000 times, and viewing area is 40 μm × 40 μm.Image analysis is carried out to the metal structure photograph taken with SEM, measures respectively for martensite and bainite (not distinguishing both) and ferritic area ratio.In table 3, α represents ferrite, (B+M) represent (bainite+martensite).And in table 3, the area ratio of " other " tissue deducts martensite and bainite and ferritic each area ratio from 100 area % and calculates.At random 3 visuals field are observed, calculate mean value.
(5) measuring method of tension test
The mode that the direction vertical with the rolling direction of conveying coated steel sheet and the long side direction of test piece are parallel to each other acquires JIS13 B tensile test specimen, determines tensile strength (TS) and the yield stress (YS) in C direction according to JISZ2241.Yield ratio YR (YS/TS) is calculated according to TS and YS.
In the present embodiment, the tensile strength TS of more than 980MPa is evaluated as high strength (qualified).In addition, the YR of more than 60% is evaluated as shock-resistant absorptivity excellence (qualified).
(6) bending machining test
Prepare the test piece of the 20mm × 70mm cut out from coated steel sheet in the mode that the long side direction of vertical direction, the rolling direction of conveying coated steel sheet and test piece is parallel to each other, carry out 90 ° of V-type pliability tests to make bending crest line along the mode of long side direction.By changing radius of curvature R aptly to implement test, obtain can not allow test piece produces fracture state under carry out the minimum bending radius Rmin of bending machining.
Based on Rmin divided by the thickness of slab t of base steel sheet the Rmin/t of gained, have rated bendability respectively by each tensile strength TS.Following in detail.In addition, TS is not met to the test piece of qualified more than benchmark 980MPa, do not evaluate bendability (being designated as "-" in table 3).
When TS is more than 980MPa and is less than 1080MPa, using Rmin/t < 1.0 as qualified
When TS is more than 1080MPa and is less than 1180MPa, using Rmin/t < 1.5 as qualified
When TS is more than 1180MPa, using Rmin/t < 2.50 as qualified
(7) delayed fracture resistance characteristics test
The section at the W/4 position vertical relative to the plate of coated steel sheet wide W direction is exposed, cut out the test piece of 150mm (W) × 30mm (L), after carrying out U-shaped bending machining with minimum bending radius, with screw fastening, the outer surface of U-shaped bending machining test piece is applied with to the tensile stress of 1000MPa.Strainometer is attached to the outside of U-shaped bending machining test piece, and strain is scaled tensile stress to determine tensile stress.Then, cover the edge part of U-shaped bending machining test piece, carried out filling hydrogen with electrochemical means.Filling hydrogen is that test piece is immersed in 0.1M-H 2sO 4(pH=3) with the mixing solutions of 0.01M-KSCN, in room temperature and 100 μ A/mm 2constant current condition under carried out.
According to described result of filling hydrogen test, the news commentary valency that do not rupture 24 hours is qualified that is delayed fracture resistance characteristics excellence.
(8) drifiting test
Implement drifiting test according to Nippon Steel alliance specification JFST1001, determine λ.Specifically, in coated steel sheet upper punch, diameter is the hole of 10mm, then, to be pressed in this hole by 60 ° of circular cone drifts, to determine the critical hole diameter that crackle produces under the state around fixing.Obtained critical hole expansibility λ (%) according to following formula, it is qualified to be evaluated as when λ is more than 25%, that is hole expandability is excellent.
Critical hole expansibility λ (%)={ (Df-D0)/D0} × 100
In formula, Df is the critical hole diameter (mm) that crackle produces, and D0 is initial hole diameter (mm)
(9) plating appearance
The outward appearance of coated steel sheet by visual inspection, it is qualified to be evaluated as when not observe and fail the position of plating, that is plating is excellent.
These results are recorded in table 2 and table 3.
Table 1
Table 2
(*), after being cooled to 600 DEG C with 10 DEG C/sec, water-cooled is carried out
Table 3
Can investigate as described below according to each table.
First, No.1 to No.11, No.18, No.20, No.23, No.25, No.27 are the examples meeting prerequisite of the present invention, and intensity, processibility [bendability and hole expandability (λ)], delayed fracture resistance characteristics, impact characteristics, plating are all good.Particularly the mean depth d of inner oxide layer and the mean depth D of soft layer meet D > 2d (that is, in table 2, the value of " D > 2d " is more than 1) the No.1 (D > 2d=1.09) of relation, compared with the No.20 (D > 2d=0.91) not meeting described relation, bendability improves.In addition, λ also increases.
On the other hand, No.12 is the example that C content is many, and bendability, λ and delayed fracture resistance characteristics reduce.
No.13 is the poor example of Si, does not fully generate inner oxide layer, and bendability, λ and delayed fracture resistance characteristics reduce.
No.14 is the poor example of Mn, and hardenability is poor, therefore generates ferrite too much, and the total amount of (B+M) also tails off.Result causes TS and YR to reduce, and λ also reduces.
No.15 is the slow example of the average cooling rate after soaking, generate ferrite too much, and the total amount of (B+M) also tails off, could not obtain desired hard layer in cooling.Result causes TS and YR step-down, and λ reduces.
No.22 is also the slow example of the average cooling rate after soaking, generates ferrite too much, therefore YR step-down in cooling, and λ, bendability, delayed fracture resistance characteristics reduce.
No.16 and No.17 is the example that the coiling temperature of hot rolling is low, pickling, cold rolling after the mean depth of inner oxide layer shallow, the mean depth d of the inner oxide layer therefore after plating, the mean depth D of soft layer also shoal.Result causes bendability, delayed fracture resistance characteristics and plating to reduce.
The air-fuel ratio of No.19 in oxidized still is low, does not fully generate ferroelectric oxide film, and plating reduces.In addition, also fully do not generate soft layer, therefore bendability, delayed fracture resistance characteristics also reduce.
No.21 is the example that soaking temperature is low, anneals in two-phase region, generates ferrite too much, and the total amount of (B+M) also tails off, and could not obtain desired hard layer.Therefore, YR step-down, λ, bendability, delayed fracture resistance characteristics reduce.
No.24 is the example of pickling time length, and inner oxide layer dissolves, and could not obtain the mean depth d of desired inner oxide layer and the mean depth D of soft layer and shoal.Result causes bendability, delayed fracture resistance characteristics, plating to reduce.
No.26 is the example that the coiling temperature of hot rolling is low, pickling, cold rolling after the mean depth of inner oxide layer shallow, the mean depth d of the inner oxide layer therefore after plating, the mean depth D of soft layer also shoal.Result causes bendability, delayed fracture resistance characteristics and plating to reduce.
No.28 is the insufficient example of soaking time, pickling, cold rolling after the mean depth of inner oxide layer shallow, the mean depth d of the inner oxide layer therefore after plating, the mean depth D of soft layer also shoal.Result causes bendability, delayed fracture resistance characteristics and plating to reduce.
Description of reference numerals
1 coating layer
2 base steel sheet
3 inner oxide layers
4 soft layers
5 hard layers
6 is inner

Claims (5)

1. a high strength coated steel sheet, has dip galvanized or alloyed hot-dip zinc-coated layer, it is characterized in that on the surface of base steel sheet,
(1) described base steel sheet is in mass % containing C:0.05% to 0.25%, Si:0.5% to 2.5%, Mn:2.0% to 4%, P: more than 0% and less than 0.1%, S: more than 0% and less than 0.05%, Al:0.01% to 0.1%, N: more than 0% and less than 0.01%, surplus is iron and inevitable impurity
(2) from the interface between described base steel sheet and described coating layer, basad steel plate side comprises successively:
Inner oxide layer, comprises the oxide compound be selected from by least one in the group that Si and Mn is formed;
Soft layer, comprises described inner oxide layer, and, when the thickness of slab of described base steel sheet is set to t, there is the Vickers' hardness of less than 90% of the Vickers' hardness at the t/4 position of described base steel sheet; And
Hard layer, comprises the tissue based on martensite and bainite, wherein,
The mean depth D of described soft layer is more than 20 μm, and the mean depth d of described inner oxide layer is more than 4 μm and is less than described D,
The tensile strength of described coated steel sheet is more than 980MPa.
2. high strength coated steel sheet according to claim 1, is characterized in that,
Described base steel sheet is further containing being selected from by Cr in mass %: more than 0% and less than 1%, Mo: more than 0% and less than 1%, B: more than 0% and less than 0.01%, Ti: more than 0% and less than 0.2%, Nb: more than 0% and less than 0.2%, V: more than 0% and less than 0.2%, Cu: more than 0% and less than 1% and Ni: at least one more than 0% and in less than 1% group formed.
3. high strength coated steel sheet according to claim 1 and 2, is characterized in that,
The mean depth d of described inner oxide layer and the mean depth D of described soft layer meets the relation of D > 2d.
4. a manufacture method for high strength coated steel sheet, is characterized in that, for the manufacture of high strength coated steel sheet according to claim 1 and 2, and comprises successively:
Hot-rolled step, will meet the coiler plate of the composition of steel of described base steel sheet at the temperature more than 600 DEG C;
Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm;
Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And
Soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.
5. a manufacture method for high strength coated steel sheet, is characterized in that, for the manufacture of high strength coated steel sheet according to claim 1 and 2, and comprises successively:
Hot-rolled step, will meet the coiler plate of the composition of steel of described base steel sheet at the temperature more than 500 DEG C;
Incubation step, is incubated more than 80 minutes at the temperature more than 500 DEG C;
Pickling and cold-rolling step, carries out pickling and cold rolling in the mode making the mean depth d of inner oxide layer retain more than 4 μm;
Oxidation step, in zone of oxidation, is oxidized with the air-fuel ratio of 0.9 to 1.4; And
Soak step, in zone of reduction, at Ac 3point is to Ac 3soaking is carried out in the scope of point+100 DEG C.
CN201480035852.2A 2013-07-12 2014-07-02 Plating, processability and the excellent high intensity coated steel sheet of delayed fracture resistance characteristics and its manufacture method Expired - Fee Related CN105324506B (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
JP2013147031 2013-07-12
JP2013-147031 2013-07-12
JP2014-068539 2014-03-28
JP2014068539A JP2015034334A (en) 2013-07-12 2014-03-28 High-strength plated steel sheet excellent in platability, processability and delayed fracture resistance characteristics and production method thereof
PCT/JP2014/067663 WO2015005191A1 (en) 2013-07-12 2014-07-02 High-strength plated steel sheet having superior plating properties, workability, and delayed fracture resistance, and method for producing same

Publications (2)

Publication Number Publication Date
CN105324506A true CN105324506A (en) 2016-02-10
CN105324506B CN105324506B (en) 2018-02-09

Family

ID=52279876

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201480035852.2A Expired - Fee Related CN105324506B (en) 2013-07-12 2014-07-02 Plating, processability and the excellent high intensity coated steel sheet of delayed fracture resistance characteristics and its manufacture method

Country Status (7)

Country Link
US (1) US20160160335A1 (en)
EP (1) EP3020842B1 (en)
JP (1) JP2015034334A (en)
KR (1) KR101754543B1 (en)
CN (1) CN105324506B (en)
MX (1) MX2016000266A (en)
WO (1) WO2015005191A1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108070795A (en) * 2016-11-18 2018-05-25 北方工业大学 Steel structural material for large-span space
CN108070791A (en) * 2016-11-18 2018-05-25 北方工业大学 High-strength anchor rod for mine reinforcement
CN110168125A (en) * 2017-02-20 2019-08-23 日本制铁株式会社 High-strength steel sheet
CN110177894A (en) * 2017-02-20 2019-08-27 日本制铁株式会社 High-strength steel sheet
CN111485188A (en) * 2020-04-02 2020-08-04 鞍钢股份有限公司 Method for improving surface platability of high-strength steel plate by adopting pre-oxidation technology
CN111886353A (en) * 2018-03-28 2020-11-03 株式会社神户制钢所 Alloyed hot-dip galvanized steel sheet and method for producing alloyed hot-dip galvanized steel sheet
CN113195776A (en) * 2018-12-19 2021-07-30 Posco公司 Galvanized steel sheet with excellent spot weldability and manufacturing method thereof
CN113544302A (en) * 2019-03-11 2021-10-22 杰富意钢铁株式会社 High-strength steel sheet and method for producing same

Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102014000969A1 (en) * 2014-01-27 2015-07-30 GM Global Technology Operations LLC (n. d. Ges. d. Staates Delaware) Motor vehicle component
JP2015193907A (en) * 2014-03-28 2015-11-05 株式会社神戸製鋼所 Alloyed high-strength hot-dip galvanized steel sheet having excellent workability and delayed fracture resistance, and method for producing the same
WO2016111275A1 (en) * 2015-01-09 2016-07-14 株式会社神戸製鋼所 High-strength plated steel sheet having excellent plating properties, workability, and delayed fracture resistance, and method for producing same
JP6010144B2 (en) * 2015-01-09 2016-10-19 株式会社神戸製鋼所 High strength plated steel sheet excellent in plating property, workability and delayed fracture resistance, and method for producing the same
JP6093412B2 (en) * 2015-01-09 2017-03-08 株式会社神戸製鋼所 High strength plated steel sheet excellent in plating property, workability and delayed fracture resistance, and method for producing the same
JP6093411B2 (en) * 2015-01-09 2017-03-08 株式会社神戸製鋼所 High strength plated steel sheet excellent in plating property, workability and delayed fracture resistance, and method for producing the same
WO2016111274A1 (en) * 2015-01-09 2016-07-14 株式会社神戸製鋼所 High-strength plated steel sheet having excellent plating properties, workability, and delayed fracture resistance, and method for producing same
JP6543732B2 (en) * 2015-05-12 2019-07-10 ポスコＰｏｓｃｏ Ultra-high strength hot rolled steel sheet excellent in bending workability and method for manufacturing the same
JP2017066508A (en) * 2015-10-02 2017-04-06 株式会社神戸製鋼所 Galvanized steel sheet for hot press and method of producing hot press formed article
KR101778385B1 (en) * 2015-11-20 2017-09-14 주식회사 포스코 High strength cold rolled steel sheet having excellent shear workability and method for manufacturing the same
KR101758485B1 (en) * 2015-12-15 2017-07-17 주식회사 포스코 High strength hot-dip galvanized steel sheet having excellent surface quality and spot weldability, and method for manufacturing the same
SE539519C2 (en) * 2015-12-21 2017-10-03 High strength galvannealed steel sheet and method of producing such steel sheet
KR102170060B1 (en) * 2016-01-27 2020-10-26 제이에프이 스틸 가부시키가이샤 High-strength galvanized steel sheet with high yield ratio and manufacturing method thereof
US11136636B2 (en) 2016-03-31 2021-10-05 Jfe Steel Corporation Steel sheet, plated steel sheet, method of production of hot-rolled steel sheet, method of production of cold-rolled full hard steel sheet, method of production of steel sheet, and method of production of plated steel sheet
CN109072375B (en) 2016-03-31 2020-11-03 杰富意钢铁株式会社 Thin steel sheet and plated steel sheet, and method for producing hot-rolled steel sheet, method for producing cold-rolled all-hard steel sheet, method for producing thin steel sheet, and method for producing plated steel sheet
KR101830527B1 (en) 2016-09-26 2018-02-21 주식회사 포스코 Cold rolled steel sheet for hot press forming and hot presse forming part having excellent corrosion property and spot weldability, and manufacturing method thereof
DE102017223633A1 (en) 2017-12-21 2019-06-27 Voestalpine Stahl Gmbh Cold-rolled flat steel product with metallic anticorrosion layer and method for producing the same
JP7137492B2 (en) 2018-03-28 2022-09-14 株式会社神戸製鋼所 Alloyed hot-dip galvanized steel sheet and method for producing alloyed hot-dip galvanized steel sheet
US11613789B2 (en) 2018-05-24 2023-03-28 GM Global Technology Operations LLC Method for improving both strength and ductility of a press-hardening steel
CN112534078A (en) 2018-06-19 2021-03-19 通用汽车环球科技运作有限责任公司 Low density press hardened steel with enhanced mechanical properties
WO2020196060A1 (en) 2019-03-28 2020-10-01 日本製鉄株式会社 High-strength steel sheet
US11530469B2 (en) 2019-07-02 2022-12-20 GM Global Technology Operations LLC Press hardened steel with surface layered homogenous oxide after hot forming
US20230087014A1 (en) 2020-03-16 2023-03-23 Nippon Steel Corporation Steel sheet
KR20220134777A (en) 2020-06-08 2022-10-05 닛폰세이테츠 가부시키가이샤 Steel plate and its manufacturing method
DE102020214293B4 (en) 2020-11-13 2022-09-15 Thyssenkrupp Steel Europe Ag Steel flat product with improved zinc coating
WO2022191008A1 (en) * 2021-03-08 2022-09-15 株式会社神戸製鋼所 Method for manufacturing hot-dip galvanized steel sheet and method for manufacturing alloyed hot-dip galvanized steel sheet
CN116802334A (en) * 2021-03-10 2023-09-22 日本制铁株式会社 Cold-rolled steel sheet and method for producing same
KR20230125023A (en) * 2021-03-10 2023-08-28 닛폰세이테츠 가부시키가이샤 Cold-rolled steel sheet and its manufacturing method
WO2023013372A1 (en) 2021-08-02 2023-02-09 日本製鉄株式会社 High-strength steel sheet
DE102021128327A1 (en) 2021-10-29 2023-05-04 Voestalpine Stahl Gmbh COLD ROLLED STEEL FLAT PRODUCT WITH METALLIC ANTI-CORROSION COATING AND PROCESS FOR MANUFACTURING SUCH
WO2023094856A1 (en) 2021-11-24 2023-06-01 Arcelormittal Zinc coated mn-containing advanced high strength steel and method of manufacturing the same

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09310148A (en) * 1996-05-20 1997-12-02 Kawasaki Steel Corp High strength cold rolled steel sheet
JPH10130782A (en) * 1996-11-01 1998-05-19 Nippon Steel Corp Ultrahigh strength cold rolled steel sheet and its production
JP2007211279A (en) * 2006-02-08 2007-08-23 Nippon Steel Corp Ultrahigh strength steel sheet having excellent hydrogen brittleness resistance, method for producing the same, method for producing ultrahigh strength hot dip galvanized steel sheet and method for producing ultrahigh strength hot dip alloyed galvanized steel sheet
JP2008024972A (en) * 2006-07-19 2008-02-07 Nippon Steel Corp High-strength hot-dip galvannealed steel sheet superior in chipping resistance
WO2011025042A1 (en) * 2009-08-31 2011-03-03 新日本製鐵株式会社 High-strength hot-dip galvanized steel sheet and process for producing same
CA2850195A1 (en) * 2011-09-30 2013-04-04 Nippon Steel & Sumitomo Metal Corporation High-strength hot-dip galvanized steel sheet excellent in impact resistance property and manufacturing method thereof, and high-strength alloyed hot-dip galvanized steel sheet and manufacturing method thereof
WO2013100615A1 (en) * 2011-12-28 2013-07-04 Posco High-strength hot-dip galvanized steel sheet having excellent plating surface quality and adhesion, and method of manufacturing the same

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5636727B2 (en) 2010-04-27 2014-12-10 新日鐵住金株式会社 Hot-dip galvanized steel sheet and manufacturing method thereof
PL2762585T3 (en) * 2011-09-30 2020-01-31 Nippon Steel Corporation High-strength hot-dip galvanized steel sheet with excellent mechanical cutting characteristics, high-strength alloyed hot-dip galvanized steel sheet, and method for producing said sheets

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09310148A (en) * 1996-05-20 1997-12-02 Kawasaki Steel Corp High strength cold rolled steel sheet
JPH10130782A (en) * 1996-11-01 1998-05-19 Nippon Steel Corp Ultrahigh strength cold rolled steel sheet and its production
JP2007211279A (en) * 2006-02-08 2007-08-23 Nippon Steel Corp Ultrahigh strength steel sheet having excellent hydrogen brittleness resistance, method for producing the same, method for producing ultrahigh strength hot dip galvanized steel sheet and method for producing ultrahigh strength hot dip alloyed galvanized steel sheet
JP2008024972A (en) * 2006-07-19 2008-02-07 Nippon Steel Corp High-strength hot-dip galvannealed steel sheet superior in chipping resistance
WO2011025042A1 (en) * 2009-08-31 2011-03-03 新日本製鐵株式会社 High-strength hot-dip galvanized steel sheet and process for producing same
CN102482753A (en) * 2009-08-31 2012-05-30 新日本制铁株式会社 High-strength hot-dip galvanized steel sheet and process for producing same
CA2850195A1 (en) * 2011-09-30 2013-04-04 Nippon Steel & Sumitomo Metal Corporation High-strength hot-dip galvanized steel sheet excellent in impact resistance property and manufacturing method thereof, and high-strength alloyed hot-dip galvanized steel sheet and manufacturing method thereof
WO2013100615A1 (en) * 2011-12-28 2013-07-04 Posco High-strength hot-dip galvanized steel sheet having excellent plating surface quality and adhesion, and method of manufacturing the same

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108070795A (en) * 2016-11-18 2018-05-25 北方工业大学 Steel structural material for large-span space
CN108070791A (en) * 2016-11-18 2018-05-25 北方工业大学 High-strength anchor rod for mine reinforcement
CN108070791B (en) * 2016-11-18 2021-12-21 北方工业大学 High-strength anchor rod for mine reinforcement
CN110168125B (en) * 2017-02-20 2021-11-26 日本制铁株式会社 High-strength steel plate
CN110177894B (en) * 2017-02-20 2021-11-19 日本制铁株式会社 High-strength steel plate
CN110177894A (en) * 2017-02-20 2019-08-27 日本制铁株式会社 High-strength steel sheet
CN110168125A (en) * 2017-02-20 2019-08-23 日本制铁株式会社 High-strength steel sheet
CN111886353A (en) * 2018-03-28 2020-11-03 株式会社神户制钢所 Alloyed hot-dip galvanized steel sheet and method for producing alloyed hot-dip galvanized steel sheet
CN111886353B (en) * 2018-03-28 2022-02-22 株式会社神户制钢所 Alloyed hot-dip galvanized steel sheet and method for producing alloyed hot-dip galvanized steel sheet
CN113195776A (en) * 2018-12-19 2021-07-30 Posco公司 Galvanized steel sheet with excellent spot weldability and manufacturing method thereof
CN113195776B (en) * 2018-12-19 2023-02-24 Posco公司 Galvanized steel sheet with excellent spot weldability and manufacturing method thereof
CN113544302A (en) * 2019-03-11 2021-10-22 杰富意钢铁株式会社 High-strength steel sheet and method for producing same
CN113544302B (en) * 2019-03-11 2022-11-18 杰富意钢铁株式会社 High-strength steel sheet and method for producing same
CN111485188A (en) * 2020-04-02 2020-08-04 鞍钢股份有限公司 Method for improving surface platability of high-strength steel plate by adopting pre-oxidation technology

Also Published As

Publication number Publication date
EP3020842A4 (en) 2017-03-15
WO2015005191A1 (en) 2015-01-15
CN105324506B (en) 2018-02-09
EP3020842B1 (en) 2019-03-13
EP3020842A1 (en) 2016-05-18
MX2016000266A (en) 2016-04-20
KR101754543B1 (en) 2017-07-06
KR20160030295A (en) 2016-03-16
JP2015034334A (en) 2015-02-19
US20160160335A1 (en) 2016-06-09

Similar Documents

Publication Publication Date Title
CN105324506A (en) High-strength plated steel sheet having superior plating properties, workability, and delayed fracture resistance, and method for producing same
CN106133164B (en) Processability and the excellent high-strength and high-ductility galvannealed steel sheet of delayed fracture resistance characteristics and its manufacture method
KR101605980B1 (en) High-strength hot-dip galvanized steel sheet having excellent delayed fracture resistance, and method for producing same
CN103210105B (en) Uniform elongation and the excellent high-strength hot-dip zinc-coated steel sheet of plating and manufacture method thereof
KR101843703B1 (en) Plating steel sheet excellent in plating property, workability and delayed fracture resistance, and manufacturing method thereof
CN107075644B (en) High-strength steel sheet and its manufacturing method
CN101646797B (en) High-strength hot-dip zinc-coated steel sheet
CN101903556B (en) Processes for producing high-strength hot-dip galvanized steel sheet and high-strength galvannealed steel sheet
US20180002799A1 (en) High-strength plated steel sheet and method for producing same
KR101843705B1 (en) Plating steel sheet excellent in plating property, workability and delayed fracture resistance, and manufacturing method thereof
US20180010207A1 (en) High-strength plated steel sheet and method for producing same
KR101843704B1 (en) Plating steel sheet excellent in plating property, workability and delayed fracture resistance, and manufacturing method thereof
KR101730292B1 (en) Cold-rolled steel plate, galvanized cold-rolled steel plate, and method for manufacturing said plates
JP2018193614A (en) High strength plating steel sheet excellent in plating property, processability and delayed fracture resistance, and manufacturing method therefor
WO2016111275A1 (en) High-strength plated steel sheet having excellent plating properties, workability, and delayed fracture resistance, and method for producing same
CN107849666A (en) Steel plate, hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel plate and their manufacture method
JP5338873B2 (en) High-strength hot-dip galvanized steel sheet excellent in workability with a tensile strength of 440 MPa or more and its production method
WO2016111274A1 (en) High-strength plated steel sheet having excellent plating properties, workability, and delayed fracture resistance, and method for producing same
KR102508292B1 (en) High-strength steel sheet and its manufacturing method
JP2013036071A (en) High strength hot dip galvanized steel sheet excellent in workability with tensile strength of at least 440 mpa and method for producing the same
KR20140139057A (en) Hot-dip galvanized steel sheet for stamping having excellent cold workability, die hardenability, and surface quality, and producing method thereof
CN109689910A (en) Steel plate

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20180209

Termination date: 20200702

CF01 Termination of patent right due to non-payment of annual fee